Refrigerated display case



y 1962 ca. w. MATHIS ETAL 3,

REFRIGERATED DISPLAY CASE 3 Sheets-Sheet 1 Filed June 27, 1960 INVENTOR.GLENN.W.MATH|$ BY RALPH.J. BURGER July 17, 1962 Filed June 27, 1960 G.W. MATHIS ET AL REFRIGERATED DISPLAY CASE 3 Sheets-Sheet 3 INVENTOR.GLENN.W. MATHIS RALPH. J. BURGER 3,044,274 REFRIGERATED DISiLAY CASEGlenn W. Mathis and Ralph J. Burger, Kendallville, Ind.,

assignors to McCray Refrigerator Company, Inc., Kendallville, End, acorporation of Indiana Filed June 27, 1960, Ser. No. 39,147 7 Claims.(Cl. 62-256) The present invention rel-ates broadly to refrigerateddisplay cases, and, more particularly, relates to a novel combinationopen-front refrigerated display and storage case for use in theself-service merchandising of refrigerated products and the like, andespecially to the air circulating and distributing characteristicsthereof.

The primary object of the present invention is the provision of arefrigerated case combining in a single unit a refrigerated open-frontdisplay area or compartment and a closable storage area or compartmentfrom which the stock in the display area can be replenished, both servedby a common, novel air cooling and circulating system whereby thecommercial value and efliciency of the display and sales compartment andits associated storage and stocking compartment are greatly enhanced.

A further object of the invention is the provision of a. refrigerateddisplay case of the above type having hori: zontally extending,vertically spaced shelves in the openfront display compartment uponwhich products to be purchased are positioned.

It is a still further object of the invention to provide a refrigerateddisplay case of the above type in which a large, walk-in type storagecompartment is located immediately rearward of an open-front displaycompartment, the storage and display compartments being separated by atleast partially perforated door sections whereby such perforations aidin directing cool air over shelves posi tioned in the displaycompartment, and such door sections providing, when opened, an access tothe display compartment from the storage compartment through which theshelves may be stocked from the rear.

Another object of the invention is to provide a refrigeration system inwhich discharge air from the open front display section is cooled priorto being circulated through the storage section, in addition to beingcooled during its residence in the storage compartment, the lattercooling serving to extract heat given up by the stored merchandise.

Other objects and advantages will in part be apparent, and will in partappear hereinafter.

For a better understanding of the nature and objects of the invention,reference should be had to the following detailed description andaccompanying drawings illustrating preferred embodiments thereof, inwhich:

FIG. 1 is a front elevation, with certain parts broken away, of adisplay case embodying the present invention;

FIG. 2 is a vertical sectional view taken along the line 2-2 of FIG. 1;

FIG. 3 is a fragmentary detail view taken along the line 3-3 of FIG. 2;and

FIG. 4 is a vertical sectional view of a slightly modified form ofdisplay case embodying thepresent invention.

Referring now to the drawings, and particularly to FIGS. 1-3, therefrigerated case therein disclosed is formed by a bottom wall 10, aback or rear wall 11, a

top wall 12, end walls 13, and a front wall 14. These' walls are all ofsuitable insulated construction, as is common in cases of this type.

The front wall 14 is provided with a large opening 15 therein to providecustomer access into a display compartment 16, aluminum or the like trim17 being employed for decorative purposes if desired. The displaycompartment 16 is defined by top and bottom panels 18 and 19 3,644,??4Patented July 17, 19 62 "ice 2 respectively, the top panel 18 comprisingan insulated section. The rear or back wall of the display compartmentcomprises, at least in part, a plurality of door sections 20 mounted forrelative sliding movements lengthwise of the case to permit any sectionto be moved to provide an opening into a storage compartment 21 throughwhich the contents of the display compartment maybe received from therear and the merchandise in the case replenished or stocked. The doorsections may lap each other to permit a sliding of one past the other,and to this end the sections may operate in guide channel members 22 and23 at the top and bottom of the display compartment. The door sections20 are perforated over a substantial portion of their area as indicatedat 24 to provide essential air flow between the storage and displaycompartments when the door sections are in the normally closed position,The function and purpose of these perforated door portions will be subsequentially explained in more detail.

A plurality of vertically spaced shelves such as shown at 25, 26 and 27are provided in the display compartment '16 and extend lengthwisetherein to form the supporting means for various food products. Theshelves are supported by several spaced, parallel, vertical support members 28 positioned forwardly adjacent the door sections 20, and bybrackets 29 fixed therein. The brackets 29 may be fixed to the supportmembers in any suitable fashion, and, for purposes of disclosure, areshown as having prongs 30 which cooperate with slots in the verticalsupport members, such as shown at 31, in a manner 'well known in theart. The shelves may be either solidv provided with a light source asindicated at 35.

Located in the storage compartment 21 in that portion thereof overlyingthe display compartment 16, an air circulating fan 36 driven by arespective motor 37. The fan 36 is mounted 'by a bracket 38 and inducesair flow from the storage. compartment 21 into a plenum chamber 39 andin the rear of such chamber to contact vw'th a set of cool ing coils 40of a refrigerating system. The cooling coils,

which preferably extend substantially throughout the length of thedisplay case, are disposed in'a box or frame 41 which -is open at itsfront to the plenum chamber 39 and at its rear to the top of an inletflue 42. The in let fine 42 extends downwardly between the panel 18 andthe channel member 22 and opens into the display compartment 16 alongits length through a perforated face plate 43 in the upper rear portionthereof and an opening or aperture 43a between the panel 18 and the faceplate I the display compartment. The bottom of the outletfiue 45. isformed by a partition 46, an air circulating fan 47 48 located beneaththe partition 46 so that the air circuv 43.- The face plate 43 isslanted in such a direction that cool air flowing therethrough isdirected substantially downward over the topmost shelf 27, while airflowing through the opening 43a moves forwardly in the compartment 16.;p A partition 44 extends upwardly from the forward edge of the panel 19in rearwardlyspaced relation to the front wall 14 to form an outlet flue45 in the bottom front portion thereof preferably extending the entirelength of being located in a perforated recess thereof, preferablyapproximately in the center of the display case. The perforated recesscommunicates with a plenum chamber i duced by gravity.

la-ting fan induces air, warmed by contact with the merchandise in thedisplay compartment, into and through the outlet flue 45 into the plenumchamber 48 and thence in the rear of such chamber to contact with a setof cooling coils 49 of a refrigerating system. Thecooling coils 49 aresubstantially coextensive with the length' of the display compartmentand are disposed in a box or frame 50 which is open at its front to theplenum chamber 48 and at its rear to the storage comp'artment'21 througha 'heightis preferably such as to allow a person of average height toWalk into it conveniently. The storage compartrnent may be provided-withaplurality of foraminous or 7 solid shelves 52 affixed on the rear wall11 'inany suitable manner and upon which foodlproducts used to restockthe display compartment are supported.

An air circulating fan 53 driven by a respective motor 54 is provided atthe upper rear of the storage compartment in aproximately the centerthereof. The fan 53 induces' 'air in the storage compartment '21 to flowadjacent'to and in contact with another set of cooling coils SS-of arefrigerating system. "The cooling coils 55 are disposed in aconventional box orframe 56 having an opening inits bottom'in which theair circulating fan 53' is disposed, and an outlet at its forward endprovided with directional vanes 57 for directing cool air flow outwardlyand downwardly therefrominto the storage compartment.

- The frame 56 and the cooling coils 55 need only extend partially alongthe length of the. storage compartment as ings. In passing downwardly infront of or through, as

the'case may be, the shelves 26 and 25, this air additionally flowsforwardly and adjacent the air cascading 'over the ends of these shelvesresulting from the flow of air from the storage compartment 21 throughthe per- 1 forations 24 in the door sections 20. This air, cascadingover the ends of the shelves 25 and 26 and warmed by contact with thefood products thereon, is of relatively illustrated. In this respect,the fan 53 maybe eliminated if desired and contact of thestoragecompartment air with the coils 55 made. solely dependent uponflow in- As was previously noted, the door sections 20 are perforatedover a substantial portion of their area. Prefer; ably,theseperfora-tions extend'over the door sections I from a heightapproximately equal to the top of the uppermost shelf 27 and downwardlyto approximately midway between the bottom of the display compartmentandthe lower shelf 25 although they may 'extend completely thereover ifdesired. These perforations enable cold air in the storage compartmentto how therethrough and adjacent the food products positioned upon theshelves 25 and 26 and panel 14 in a manner now to be explained. Itshould be understood that any type of perforated division may beemployed between the. compartments, the specific disclosure ofthesliding door sections being for purposes of illustration only. Forexample, doors which are hinged to pivot vertically or horizontally maybe successfully utilized, as well as merely a perforated curtain whichcould be raised'and lowered as desired.

'. is forced outwardly from the inlet fiuetlhroughthe openor aperturesin the face plate 43 and through the opening 43a, thence downwardly overthe food products positioned on the topmost shelf 27 to effectively coolthe same. This air then flows, partially from its own mornentumresulting from the fan '36 and partially drawn by gravity and by theaction of the fan 47, downwardly over the front of the displaycompartment and shelves low velocity and spills over the front of thedisplay shelves and is drawn downwardly into the bottom of the displaycompartment, its downward flow being induced by gravity and also bysuction from the air circulating fan 47 located in the inlet fine 44.

The mass of air resulting from the combined air streams described abovenext flows through the outlet flue at the bottom of the displaycompartment and is forced by the fan 47 into the plenum chamber 48 andthence over and around the cooling coils 49 disposed in the box or frame50. Thus the return air is cooled prior to'its entry into the storagecompartment 21. After passing through the passageway 51, .a portion ofthe cold return air is directed upwardly in the storage compartmentadjacent theperforated door sections 26 by the baffle plate 51a and theremaining portion of this cold return air flows over the bafiie plateinto the lower portion of the storage compartment creating, togetherwith the cold air flowing from contact with the cooling coils 55 in theupper rear portion of the storage compartment 21, a generally turbulentand Well mixed cold mass of air.

The turbulent mass of cold air in the storage compartment effectivelyextracts heat from and cools the stored food products positioned on theshelves 52, the warmer air resulting from such heat extractionraising inthe storage compartment partially under the force of gravity andpartially by the suction created by the fan 53 into contact with thecooling coils 5S inthe box or frame 56 and outwardly'therefrom againinto the storage compartment 21. In order to create and maintain the aircirculation above described and illustrated in the drawings by thearrows,

it has been found that a positive pressure must be maintained in thestorage compartment which 'at least slightly exceeds that existing inthe display compartment 16. This is preferably effected in the presentinvention by providing a fan of greater capacity in the outlet flue 44than that fan in association wth the inlet flue 42; This is important aand is one of the features in which the present invention the foodproducts thereon.

' effective, aiiording in essence individual cooling of each 26 and-25;If foraminous shelves are employed and not packed solidly with foodproducts, a small portion of this air will also how downwardly throughthe resulting open- I cooling coils and inlet flue, are eliminated.

shelf in the display compartment. v It will be apparent that, dependingupon the length of the display case, a plurality of air circulatingmeans or fans may be employed therealong in each of the positions at thetop'and bottom of the display compartment and the upper rear of thestorage compartment instead of the single means illustrated to insureproper circulation of air as above described.

In FIG. 4 of the drawings, we have shown a modified form of a displaycasein accordance with the invention. In this embodiment, the aircirculating means or fan, at the top of the display compartment 16, aswell as the It has been found that the air'circulating and distributingcharacteristics'of the modified caseare satisfactory and provide aneificient 'and economical system. In this embodiment, a panel 58 formsthetop section of the display compartment 16. i The panel 58 isperforated at the forward and rear ends thereof as indicated at 59 toprovide communication with the storage compartment 21. Theseperforations enable cold air to flow from the upper portion of thestorage compartment into the upper portion of the display compartment,as indicated by the arrows, due to the forced draft created by the aircirculating fan 47 and the positive pressure created and maintainedthereby in the storage compartment.

It has been found to be essential in the embodiment illustrated in FIG.4, that the door sections 2% be perforated over substantially theirentire height, i.e. the perforations must extend upwardly beyond the topshelf 27. In this manner, the food or dairy products on the top shelf 27are predominantly cooled by the air flowing through the doorperforations, while the flow of air through the perforations 59 in thepanel 58 is utilized chiefly to supplement the cooling effect of the airpassing through the door perforations and generally aid in themaintenance of the proper temperature in the display compartment. Asabove noted, this air flow is caused by the positive pressure maintainedin the storage compartment. Other than the differences above mentioned,the display case of FIG. 4 is substantially identical with the caseillustrated in FIGS. 1-3. In this respect, although no shelves are shownsupported on the rear wall of the storage compartment, provisions forsuch shelves can be made thereon, as well as on the side walls of thestorage compartment if desired.

It should be noted that various arrangements intermediate those shown inFIGS. 1 and 4 may also be employed without detrimentally afiecting thenovel air circulation system in accordance with the present invention.For example, satisfactory results may be obtained by providing coolingcoils adjacent the perforations 59 in FIG. 4 without employing anauxiliary fan in association therewith such as in the embodiment shownin FIGS. 1 and 2, or, conversely, by employing a fan adjacent suchperforations but no cooling coils in association therewith. In thelatter embodiment, however, care must be taken that the fan be of asmaller capacity than the lower plenum chamber fan in order that theessential positive pressure be maintained in the storage compartment. Inthis connection, it is also possible to eliminate the entire auxiliaryceiling panel 58 in the embodiment shown in FIG. 4 if desired.

Satisfactory results may also be obtained, if certain desired conditionsexist, with the elimination of the cooling coils in the lower plenumchamber. In this respect, acceptable temperatures can be maintained inthe display compartment with such an arrangement only if the relativehumidity is not excesssively high.

It will be apparent that a novel refrigerated display case has beenprovided in which a highly eflicient air circulating and distributingsystem assures effective cooling of an open front display area andstorage compartment located rearwardly thereof. While the invention hasbeen disclosed in conjunction with specific forms and disposition of theparts, it should be expressly understood that it is capable of numerousmodifications and changes without departing from the purview and scopeof the appended claims.

We claim:

1. In a refrigerated display case, an open-front dis play compartment, astorage compartment located substantially rearwardly of said displaycompartment, said display compartment having a rear wall perforate overat least a portion of its area, means including an air inlet into theupper portion of said display compartment from the upper portion of saidstorage compartment to provide an air curtain across the front of saiddisplay compartment, means forming an air outlet from the lower portionof said display compartment and opening into the lower portion of saidstorage compartment, air circulating means operatively associated withsaid outlet means for creating a forced draft of air from said displaycompartment to said storage compartment, air cooling means formaintaining cold air in said storage compartment, said air circulatingmeans being effective to create and maintain a positive pressure in saidstorage compartment whereby cold air is caused to flow from said storagecom partment through said perforate rear wall and thence into saiddisplay compartment, directly over goods in said display compartment. 7

2. In a refrigerated display case, an open-front display compartment, astorage compartment located substantially rearwardly of said displaycompartment, said display compartment having a rear wall perforate overat least a portion of its area, means including an air inlet into theupper portion of said display compartment from the upper portion of saidstorage compartment, means forming an air outlet from the lower portionof said display compartment and opening into the lower portion of saidstorage compartment, first air circulating means operatively associatedwith said inlet-including means for creating a forced draft of airfromsaid storage comp-artment to said upper portion of said displaycompartment to provide an air curtain across the front of said displaycompartment, second air circulating means operatively associated withsaid outlet means for creating a forced draft of air from said displaycompartment tosaid storage compartment, air cooling means formaintaining cold air in said storage compartment, said second aircirculating means being effective to create and maintain a positivepressure in said storage compartment whereby cold air is caused to flowfrom said storage compartment through said perforate rear wall andthence into said display compartment, directly over goods in saiddisplay compartment.

3. In a refrigerated display case, an open-front display compartment, astorage compartment located substantially rearwardly of said displaycompartment, said display compartment having a rear wall perforate overat least a portion of its area, said rearwall including means effectiveto provide access between said storage and display compartments, meansincluding inlet and distributing means for enabling cold air from saidstorage compartment to flow downwardly into the top of said displaycompartment to provide an air curtain across the front of said displaycompartment, means in the lower portion of said display compartment forcooling and returning said air to said storage compartment, and meanseffective to create and maintain a positive pressure in said storagecompartment whereby cold air is caused to flow from said storagecompartment through said perforated rear wall and thence into saiddisplay compartment, directl over goods in said display compartment.

4. In a refrigerated display case, an open-front display compartment, astorage compartment located substantially rearwardly of said displaycompartment, said display compartment having a rear wall perforate overat least a portion of its area, said rear wall including means effectiveto provide access between the said storage and display compartments, aseries of apertures extending lengthwise of said display compartment andproviding an air inlet into the upper portion of said displaycompartment from said storage compartment, an outlet flue extendinglengthwise of said display compartment and opening into said displaycompartment in the lower portion thereof, means forming a plenum chamberhaving an inlet opening into said outlet flue and an outlet opening intosaid storage compartment, first air cooling means in said plenum chamberbetween said inlet and outlet thereof, first air circulating meansimmediately forward of said plenum chamber for creating a forced draftof air from said display compartment to said storage compartment, andsecond air cooling and circulating means in said storage compartment,said first air circulating means being effective to create and maintaina positive pressure in said storage compartment whereby cold air iscaused to flow from said storage compartment through saidperforate rearwall and thence into said display compartment, directly over goods insaid display compartment.

5. Ina refrigerated display case, an open-front displaycompartmeng'a'storage compartment located substantially rearwardly ofsaid display compartment, said display compartment having a rear wallperforate over at least a portion of its area, a'n inlet flue extendinglengthwise of said display compartment and opening into said displaycompartment in the upper portion thereof, means forming a first plenumchamber having an inlet opening into said storage compartment and anoutlet opening into said inlet flue whereby air discharged from saidoutlet forms an air curtain across the fiont of said displaycompartment, an outlet flue extending lengthwise of said displaycompartment and opening into said display compartment in the lowerportion thereof, means forming a second plenum chamber having an inletopening into said outlet flue and an outlet opening'into saidstoragecompartment, air cooling means in said first plenum chamberbetween said inlet and outlet thereof and in said second plenum chamberbetween said inlet and outlet thereof,

"aircirculatingmeans immediately forward of said first and second plenumchambers for creating a forced draft mediatelyforward said first plenumchamberwhereby a positive pressure is created and maintained in saidstorage compartment causing flow of cold air from said storagecompartment through said perforate rear wall and thence into saiddisplay compartment, directly over goods in said display compartment.

6. A refrigerated display case according to claim 5 characterized byincluding a plurality of vertically spaced shelves positioned adjacentsaid door sections and extending forwardly into said displaycompartment, the perforations in said door sections extending over avertical distance from a height approximately equal to the height of thetopmost of said shelves to below the lowermost of said shelves.

7. A refrigerated display case according to claim 5 References Cited inthe file of this patent UNITED STATES PATENTS 1,448,361 Fredberg Mar.13, 1923 2,890,573 Lamb June 16, 1957 2,923,137 Swanson Feb. 2, 1960"2,961,845

Kennedy Nov. 29, 1960

